NASA Spacecraft to Pass Close to Saturn's Moon
Mon Oct 25, 2004 04:58 PM ET

LOS ANGELES (Reuters) - The NASA spacecraft Cassini, which is carrying a European Space Agency probe, cut off communications with controllers on Monday as it prepared to peer beneath a veil of smog shrouding Saturn's moon, Titan.
Cassini is set to pass within 745 miles of Titan's surface at about 12:45 p.m. (2:45 p.m. EDT) Tuesday, in the closest pass ever to the mysterious icy moon, whose atmosphere scientists have likened to a primordial Earth.

Cassini will snap infrared and radar images 100 times sharper than any taken so far of Titan, said scientists at NASA's Jet Propulsion Laboratory in Pasadena, California.

Carrying the European Space Agency probe called Huygens, Cassini is supposed to resume contact with NASA controllers on Tuesday evening. It will download data and images collected during its pass near Titan -- one of 45 planned for the spacecraft's four-year tour of Saturn and its moons.

Titan is the only known moon with an atmosphere. It is believed to have oceans of liquid methane and ethane on its frozen surface and a nitrogen-rich atmosphere that may hold clues to how Earth's atmosphere evolved.

"What we've got is a very primitive atmosphere that has been preserved for 4.6 billion years. Titan gives us the chance for cosmic time travel ... going back to the very earliest days of Earth when it had a similar atmosphere," said Toby Owens, principal scientist at the Jet Propulsion Laboratory.